A green “0% commission” sign at the Marrakech airport almost cost me 8% on every euro I exchanged. Here’s how the airport currency exchange trick actually works, and what I do at every arrivals hall now instead.

I used to just wing it with rental cars, until years of solo pickups in Bratislava and one week driving the Azores taught me what actually matters. Here’s what I wish I’d known before booking my first one alone.